Autism is the term for a symptom-complex of a subject meaning such a bad communication possibility with people around that the subject in question has to be taken care of by the society in different ways during its whole lifetime.
One to five out of 1000 persons born in Sweden suffer from autism. The diagnosis is difficult to establish and can take several years to secure. The pedagogical and social measures, which the society and the family of the autistic person have to take, are lifelong and extremely costly. The suffering of the ones affected and their families is great. No biochemical treatment is known (e.g., use of pharmaceuticals) so far.
The pathophysiology of autism involves abnormal communication between neurons, possibly associated with abnormal patterns peptides, e.g., neuropeptides in the brain. Abnormal levels of peptides might be revealed by proteomic studies of proteins/peptides below 10 kDa in spinal fluid and/or blood plasma. Detection of abnormal levels of peptides in autism will allow generation of new hypotheses concerning its pathophysiology and might facilitate diagnostics and suggest new treatment possibilities. Since most peptides are generated by proteolysis of larger precursor molecules abnormal levels of peptides might be caused by abnormal proteolytic activity.
There is very little biochemical research done and available concerning autism as there are no animal models available and there is a practical problem collecting a more substantive patient material.
In the prior art EP-A-0 979 828 discloses a method for diagnosing autism by determining specific peptides present in a biological fluid. The peptides which comprises 3 to 4 amino acids are said to indicate autism when present in high amounts.
EP-A-0 969 015 relates to a method for diagnosing a disease, such as autism, by identifying peptides present in a tissue of body liquid. The peptides are disclosed as having a length of 3 to 8 amino acids, and having a molecular weight of <1081.
Green, L. A. et al in Biological Psychiatry, 50: 609-613 (2001) discloses that the oxytocin concentration in plasma of autistic persons is different from the one in healthy persons. The amount of oxytocin-extened (OT-X) is higher in autistic patients, while the amount of oxytocin (9 amino acids) is lower.
US-A-2002/0006640 relates polypeptides and methods for diagnosis of inter alia autism.
None of these documents discloses the peptides of the present invention.